Starfire,

I wouldn’t say the books are “RARE” – but they’re getting harder to find. Abebooks and Amazon are probably your best shots at finding a copy. Not to long ago I saw a copy of the “Stirling Files” and “The Whitley Files” on Ebay…
I found a copy of “The Lancaster Files” at Abebooks a few months back. It was well worth the price that I paid.

Cheers,

Todd